Frequency routing based on orientation

ABSTRACT

Systems, methods, and apparatus for frequency routing based on orientation are disclosed. An example method includes receiving, by a playback device, an audio data stream. The example method includes determining, by the playback device, an orientation of the playback device. The example method includes routing, by the playback device, a first set of frequencies in the audio data stream to at least one of a plurality of speaker drivers based on the first orientation. The example method includes routing, by the playback device, a second set of frequencies in the audio data stream to the at least one of the plurality of speaker drivers based on the second orientation, wherein the first set of frequencies is different than the second set of frequencies.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/688,204, filed on Aug. 28, 2017, and currently pending; U.S.application Ser. No. 15/688,204 is a continuation of U.S. applicationSer. No. 14/813,961, filed on Jul. 30, 2015, and issued as U.S. Pat. No.9,748,647 on Aug. 29, 2017; U.S. application Ser. No. 14/813,961 is acontinuation of U.S. application Ser. No. 14/684,927, filed on Apr. 13,2015, and issued as U.S. Pat. No. 9,748,646 on Aug. 29, 2017; U.S.application Ser. No. 14/684,927 is a continuation of U.S. applicationSer. No. 13/186,249, filed on Jul. 19, 2011, and issued as U.S. Pat. No.9,042,556 on May 26, 2015. The entire contents of the Ser. Nos.15/688,204; 14/813,961; 14/684,927; and 13/186,249 applications areincorporated herein by reference.

FIELD

The presently disclosed technology is directed towards technology foruse in the area of consumer electronics. In particular, certainembodiments are directed to shaping sound responsive to a speakerorientation.

BACKGROUND

Music is very much a part of our everyday lives. Thanks to theadvancement of technology, music content is now more accessible thanever. The same can be said of other types of media, such as television,movies, and other audio and video content. In fact, now a user can evenaccess the content over the Internet through an online store, anInternet radio station, online music service, online movie service, andthe like, in addition to the more traditional means of accessing audioand video content.

The demand for such audio and video content continues to surge. Giventhe high demand over the years, technology used to access and play suchcontent has likewise improved. Even still, technology used in accessingthe content and the playback of such content can be significantlyimproved or developed in ways that the market or end users may notanticipate.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentlydisclosed technology will become better understood by a person skilledin the art with regard to the following description, appended claims,and accompanying drawings where:

FIG. 1 shows an example configuration in which certain embodiments maybe practiced;

FIG. 2A shows an illustration of an example zone player having abuilt-in amplifier and speakers;

FIG. 2B shows an illustration of an example zone player having abuilt-in amplifier and connected to external speakers;

FIG. 2C shows an illustration of an example zone player connected to anA/V receiver and speakers;

FIG. 3 shows an illustration of an example controller;

FIG. 4 shows an internal functional block diagram of an example zoneplayer;

FIG. 5 shows an internal functional block diagram of an examplecontroller;

FIG. 6A shows an illustration of an example zone player in a firstposition;

FIG. 6B shows an illustration of the example zone player in FIG. 6A, butin a second position that is different from the first position;

FIG. 7A shows an illustration of an example zone player in a firstposition;

FIG. 7B shows an illustration of the example zone player in FIG. 7A, butin a second position that is different from the second position;

FIG. 8 shows an internal functional block diagram of an example zoneplayer with a sensor module for detecting orientation in accordance withan embodiment; and

FIG. 9 shows a flowchart illustrating a method for shaping sound basedon at least an orientation.

FIG. 10 shows an example orientation determination state machine.

FIG. 11 shows four regions of orientation determination based on areference horizontal orientation.

FIG. 12 illustrates an example unknown orientation region produced byvarying combinations of roll and pitch.

FIG. 13 illustrates axes of an example accelerometer with a line-drawingrepresentation in a vertical table top position.

FIG. 14 illustrates a plot of example, experimental data used todetermine minimum and maximum ranges for each axis.

FIG. 15 depicts example X, Y, and Z axes defined with respect to aplayback device.

FIG. 16 shows an example usable range of angles for an orientationdetermination.

FIG. 17 depicts an illustrative network audio system operating inaccordance with a decentralized communication, organization, and controlstructure.

In addition, the drawings are for the purpose of illustrating certainembodiments, but it is understood that the inventions are not limited tothe arrangements and instrumentality shown in the drawings.

DETAILED DESCRIPTION I. Overview

Example embodiments described herein relate to shaping sound responsiveto a speaker orientation. The embodiments are particularly useful in aplayback device that can be positioned in various ways. The embodimentsmay also find utility, for example, in connection with any environmentand system for which flexibility in orienting a speaker and optimalsound based on that orientation are desired.

In certain embodiments, an audio data stream is obtained by a playbackdevice having one or more speaker drivers, an orientation of theplayback device is determined, and sound is reproduced by the playbackdevice based on the orientation. In one embodiment, a stereophonicsignal is reproduced by a plurality of speakers based on a firstorientation, and a monaural signal is reproduced by the plurality ofspeakers based on a second orientation. In a second embodiment, aspeaker driver reproduces a monaural signal and either a right or leftchannel signal based on a first orientation, and the speaker driverreproduces only a monaural signal based on a second orientation. In athird embodiment, a speaker driver reproduces a first range offrequencies based on a first orientation, and the speaker driverreproduces a second range of frequencies based on a second orientation.In a fourth embodiment, the playback device does not contain a display.In a fifth embodiment, the playback device is an audio-only device, suchas a loudspeaker system.

In certain embodiments, sound is reproduced by a playback device basedon an orientation of the playback device and whether the playback deviceis paired with another playback device. In some instances, theorientation trumps the pairing and the sound is reproduced based on theorientation. In some instances, the pairing trumps the orientation andthe sound is reproduced based on the pairing. In some instances, boththe orientation and the pairing determine the sound reproduction.Further, the sound may be reproduced based on orientation and any of:pairing, grouping, and consolidation of playback devices.

In certain embodiments, sound is reproduced by a playback device basedon an orientation of a different playback device. For example, playbackdevice A and playback device B might be paired, such that the twoplayback devices reproduce a certain overall sound. In some instances,the sound from playback A may be based on the orientation of playbackdevice B. In some instances, the sound from playback B may be based onthe orientation of the playback device A. In some instances, the overallsound may be based on the orientation of both playback devices A and B.This is particularly useful to shape the sound coming from a collectionof different playback devices.

In certain embodiments, an audio data stream is obtained by a playbackdevice having one or more speaker drivers, an orientation of theplayback device is determined, and sound is reproduced by the playbackdevice based on the orientation. In some embodiments, the audio datastream is modified by the playback device based on the orientation. Insome embodiments, the audio data stream is modified prior to beingobtained by the playback device, yet the modification is based on theorientation.

In certain embodiments, a playback device contains one or more speakerdrivers that face (or substantially aim toward) a particular direction.In some instances, an orientation of the playback device is based on arotation about an axis that is perpendicular to the front face. That is,the one or more speaker drivers still face the particular directionregardless of the rotation. In some instances, an orientation of theplayback device is based on a rotation about an axis that is parallel tothe front face. As such, upon a rotation, the one or more speakerdrivers may face a direction that is different from the particulardirection. In some instances, an orientation of a playback device isbased on a rotation about more than one axis. According to the certainembodiments, the orientation is used to determine the sound output fromthe playback device.

An advantage of one or more embodiments described herein is that thesound field produced by one or more playback devices can be shaped basedon the orientation of one or more playback devices. The technology canbe used in any environment for which optimized sound is desired.Particularly, the technology is useful when listening to music andwatching a video, television or a movie.

Although the following discloses example methods, apparatus, systems,and articles of manufacture including, among other components, firmwareand/or software executed on hardware, it should be noted that suchmethods, apparatus, systems, and/or articles of manufacture are merelyillustrative and should not be considered as limiting. For example, itis contemplated that any or all of these firmware, hardware, and/orsoftware components could be embodied exclusively in hardware,exclusively in software, exclusively in firmware, or in any combinationof hardware, software, and/or firmware. Accordingly, while the followingdescribes example methods, apparatus, systems, and/or articles ofmanufacture, the examples provided are not the only way(s) to implementsuch methods, apparatus, systems, and/or articles of manufacture.

When any of the appended claims are read to cover a purely softwareand/or firmware implementation, at least one of the elements in at leastone example is hereby expressly defined to include a tangible mediumsuch as a memory, DVD, CD, Blu-ray, and so on, storing the softwareand/or firmware.

These embodiments and many additional embodiments are described morebelow. Further, the detailed description is presented largely in termsof illustrative environments, systems, procedures, steps, logic blocks,processing, and other symbolic representations that directly orindirectly resemble the operations of data processing devices coupled tonetworks. These process descriptions and representations are typicallyused by those skilled in the art to most effectively convey thesubstance of their work to others skilled in the art. Numerous specificdetails are set forth to provide a thorough understanding of the presentdisclosure. However, it is understood to those skilled in the art thatcertain embodiments of the present invention may be practiced withoutcertain, specific details. In other instances, well known methods,procedures, components, and circuitry have not been described in detailto avoid unnecessarily obscuring aspects of the embodiments.

Reference herein to “embodiment” means that a particular feature,structure, or characteristic described in connection with the embodimentcan be included in at least one example embodiment of the invention. Theappearances of this phrase in various places in the specification arenot necessarily all referring to the same embodiment, nor are separateor alternative embodiments mutually exclusive of other embodiments. Assuch, the embodiments described herein, explicitly and implicitlyunderstood by one skilled in the art, may be combined with otherembodiments.

II. Example Environment

Referring now to the drawings, in which like numerals may refer to likeparts throughout the figures. FIG. 1 shows an example systemconfiguration 100 in which certain embodiments described herein may bepracticed. By way of illustration, the system configuration 100represents a home with multiple zones. Each zone, for example,represents a different room or space, such as an office, bathroom,bedroom, kitchen, dining room, family room, home theater room, utilityor laundry room, and patio. While not shown here, a single zone maycover more than one room or space. One or more of zone players 102 to124 are shown in each respective zone. A zone player 102-124, alsoreferred to as a playback device, multimedia unit, speaker, and so on,provides audio, video, and/or audiovisual output. A controller 130(e.g., shown in the kitchen for purposes of illustration) providescontrol to the system configuration 100. The system configuration 100illustrates an example whole house audio system, though it is understoodthat the technology described herein is not limited to its particularplace of application or to an expansive system like a whole house audiosystem.

FIGS. 2A, 2B, and 2C show example illustrations of a zone player 200.The zone player 200 may correspond to any of zone players 102 to 124.While certain example embodiments provide multiple zone players, anaudio output may be generated using only a single zone player. Withrespect to FIG. 2A, the example zone player 200 includes a built-inamplifier (not shown in this illustration) and speakers 202. Aparticular speaker might include a tweeter, mid-range driver, orsubwoofer. In certain embodiments, the zone player 200 of FIG. 2A may beconfigured to play stereophonic audio or monaural audio. With respect toFIG. 2B, the example zone player 200 includes a built-in amplifier (notshown in this illustration) to power a set of detached speakers 204.Speakers 204 might include any type of loudspeaker. With respect to FIG.2C, the example zone player 200 does not include an amplifier, butallows a receiver 206, or another audio and/or video type device withbuilt-in amplification, to connect to a data network 128 and play audioreceived over the data network 128 via receiver 206 and speakers 204.Example zone players include a “Sonos® S5,” “PLAY: 5™”, “PLAY: 3™,”“ZonePlayer 120,” and “ZonePlayer 90,” which are offered by Sonos, Inc.of Santa Barbara, Calif. A zone player may also be referred to herein asa playback device, and a zone player is not limited to the particularexamples illustrated in FIGS. 2A, 2B, and 2C. For example, a zone playermay include a wired or wireless headphone. In another example, a zoneplayer might include a subwoofer. In an example, a zone player mayinclude or interact with a docking station for an Apple iPod™ or similardevice.

FIG. 3 shows an example illustration of a wireless controller 300 in adocking station 302. The controller 300 may correspond to thecontrolling device 130 of FIG. 1. The controller 300 is provided with atouch screen 304 that allows a user to interact with the controller 300,for example, to retrieve and navigate a playlist of audio items, controloperations of one or more zone players, and provide overall control ofthe system configuration 100. In certain embodiments, any number ofcontrollers may be used to control the system configuration 100. Thecontrollers might be wireless like wireless controller 300 or wired tothe data network 128. Furthermore, an application running on anynetwork-enabled portable devices, such as an iPhone™, iPad™, Android™powered phone, or any other smart phone or network-enabled device may beused as a controller by connecting to the data network 128. Anapplication running on a laptop or desktop PC or Mac may also be used asa controller. Example controllers include a “Sonos® Controller 200,”“Sonos® Controller for iPhone,” “Sonos® Controller for iPad,” “Sonos®Controller for Android, “Sonos® Controller for Mac or PC,” which areoffered by Sonos, Inc. of Santa Barbara, Calif. Those skilled in the artwill appreciate the flexibility of such an application and its abilityto be ported to a new type of portable device.

Referring back to the system configuration 100 of FIG. 1, a particularzone may contain one or more zone players. For example, the family roomcontains two zone players 106 and 108, while the kitchen is shown withone zone player 102. Zones may be dynamically configured by positioninga zone player in a room or space and assigning via the controller 130the zone player to a new or existing zone. As such, zones may becreated, combined with another zone, removed, and given a specific name(e.g., “Kitchen”), if so programmed. The zone players 102 to 124 arecoupled directly or indirectly to a data network, represented in thefigure by 128. The data network 128 is represented by an octagon in thefigure to stand out from other components shown in the figure. While thedata network 128 is shown in a single location, it is understood thatsuch a network may be distributed in and around the system configuration100.

Particularly, the data network 128 may be a wired network, a wirelessnetwork, or a combination of both. In one example, one or more of thezone players 102 to 124 are wirelessly coupled to the data network 128based on a proprietary mesh network. In another example, one or more ofthe zone players 102 to 124 are wirelessly coupled to the data network128 using a non-mesh topology. In yet another example, one or more ofthe zone players 102 to 124 are coupled via a wire to the data network128 using Ethernet or similar technology. In addition to the one or morezone players 102 to 124 connecting to the data network 128, the datanetwork 128 may further allow access to a wide area network, such as theInternet.

In certain embodiments, the data network 128 may be created byconnecting any of zone players 102 to 124, or some other connectingdevice, to a broadband router. Other zone players 102 to 124 may then beadded wired or wirelessly to the data network 128. For example, a zoneplayer (e.g., any of zone players 102 to 124) may be added to the systemconfiguration 100 by simply pressing a button on the zone player itself,which enables a connection to be made to the data network 128. Thebroadband router may be connected to an Internet Service Provider (ISP),for example. The broadband router may be used to form another datanetwork within the system configuration 100, which may be used in otherapplications (e.g., web surfing). The data network 128 may also be usedin other applications, if so programmed. Further, in certainembodiments, the data network 128 is the same network used for otherapplications in the household, for example.

In certain embodiments, each zone can play from the same audio source asanother zone or each zone can play from a different audio source. Forexample, someone can be grilling on the patio and listening to jazzmusic via zone player 124, while someone is preparing food in thekitchen and listening to classical music via zone player 102. Further,someone can be in the office listening to the same jazz music via zoneplayer 110 that is playing on the patio via zone player 124. In someembodiments, the jazz music played via zone players 110 and 124 isplayed in synchrony. Synchronizing playback amongst zones allows forsomeone to pass through zones while seamlessly listening to the audio.Further, zones may be put into a “party mode” such that all associatedzones will play audio in synchrony.

In certain embodiments, a zone contains two or more zone players. Forexample, the family room contains two zone players 106 and 108, and thehome theater room contains at least zone players 116, 118, and 120. Azone may be configured to contain as many zone players as desired, andfor example, the home theater room might contain additional zone playersto play audio from a 5.1 channel or greater audio source (e.g., a movieencoded with 5.1 or greater audio channels). If a zone contains two ormore zone players, such as the two zone players 106 and 108 in thefamily room, then the two zone players 106 and 108 may be configured toplay the same audio source in synchrony, or the two zone players 106 and108 may be paired to play two separate sounds in left and rightchannels, for example. In other words, the stereo effects of a sound maybe reproduced or enhanced through the two zone players 106 and 108, onefor the left sound and the other for the right sound. In certainembodiments, paired zone players may play audio in synchrony with otherzone players.

In certain embodiments, three or more zone players may be configured toplay various channels of audio that is encoded with three channels ormore sound. For example, the home theater room shows zone players 116,118, and 120. If the sound is encoded as 2.1 channel audio, then thezone player 116 may be configured to play left channel audio, the zoneplayer 118 may be configured to play right channel audio, and the zoneplayer 120 may be configured to play bass frequencies. Otherconfigurations are possible and depend on the number of zone players andthe type of audio. Further, a particular zone may be configured to playa 5.1 channel audio in one instance, such as when playing audio from amovie, and then dynamically switch to play stereo, such as when playingaudio from a two channel source.

In certain embodiments, two or more zone players may be sonicallyconsolidated to form a single, consolidated zone player. A consolidatedzone player (though comprised of multiple, separate devices) may beconfigured to process and reproduce sound differently than anunconsolidated zone player or zone players that are paired, because aconsolidated zone player will have additional speaker drivers from whichsound may be passed. The consolidated zone player may further be pairedwith a single zone player or yet another consolidated zone player. Eachplayback device of a consolidated playback device is preferably set in aconsolidated mode.

According to some embodiments, one can continue to do any of: group,consolidate, and pair zone players, for example, until a desiredconfiguration is complete. The actions of grouping, consolidation, andpairing are preferably performed through a control interface, such asusing controller 130, and not by physically connecting and re-connectingspeaker wire, for example, to individual, discrete speakers to createdifferent configurations. As such, certain embodiments described hereinprovide a more flexible and dynamic platform through which soundreproduction can be offered to the end-user.

Sources of audio content to be played by zone players 102 to 124 arenumerous. Music from a personal library stored on a computer ornetworked-attached storage (NAS) may be accessed via the data network128 and played. Internet radio stations, shows, and podcasts may beaccessed via the data network 128. Music services that let a user streamand download music and audio content may be accessed via the datanetwork 128. Further, music may be obtained from traditional sources,such as a turntable or CD player, via a line-in connection to a zoneplayer, for example. Audio content may also be accessed through AirPlay™wireless technology by Apple, Inc., for example. Audio content receivedfrom one or more sources may be shared amongst the zone players 102 to124 via the data network 128 and controller 130.

III. Example Playback Device

Referring now to FIG. 4, there is shown an example functional blockdiagram of a zone player 400 in accordance with an embodiment. The zoneplayer 400 contains a network interface 402, a processor 408, a memory410, an audio processing component 412, a module 414, an audio amplifier416, and a speaker unit 418 connected to the audio amplifier 416. FIG.2A shows an example illustration of the front side of such a zoneplayer. Other types of zone players may not include the speaker unit 418(e.g., such as shown in FIG. 2B) or the audio amplifier 416 (e.g., suchas shown in FIG. 2C). Further, it is contemplated that the zone player400 may be integrated into another component. For example, the zoneplayer 400 could be constructed as part of a lamp for indoor or outdooruse.

Referring back to FIG. 4, the network interface 402 facilitates a dataflow between zone players and other devices on a data network (e.g., thedata network 128 of FIG. 1) and the zone player 400. In someembodiments, the network interface 402 may manage the assembling of anaudio source or file into smaller packets that are to be transmittedover the data network or reassembles received packets into the originalsource or file. In some embodiments, the network interface 402 mayfurther handle the address part of each packet so that it gets to theright destination or intercepts packets destined for the zone player400. Accordingly, in certain embodiments, each of the packets includesan Internet Protocol (IP)-based source address as well as an IP-baseddestination address.

In certain embodiments, the network interface 402 may include one orboth of a wireless interface 404 and a wired interface 406. The wirelessinterface 404, also referred to as an RF interface, provides networkinterface functions for the zone player 400 to wirelessly communicatewith other devices in accordance with a communication protocol (e.g.,any of the wireless standards IEEE 802.11a, 802.11b, 802.11g, 802.11n,or 802.15). The wired interface 406 provides network interface functionsfor the zone player 400 to communicate over a wire with other devices inaccordance with a communication protocol (e.g., IEEE 802.3). In someembodiments, a zone player includes both of the interfaces 404 and 406.In some embodiments, a zone player 400 includes only the wirelessinterface 404 or the wired interface 406.

In certain embodiments, the processor 408 is a clock-driven electronicdevice that is configured to process input data according toinstructions stored in memory 410. The memory 410 is data storage thatmay be loaded with one or more software modules 414, which can beexecuted by the processor 408 to achieve certain tasks. In one example,a task might be for the zone player 400 to retrieve audio data fromanother zone player or a device on a network. In a second example, atask might be for the zone player 400 to send audio data to another zoneplayer or device on a network. In a third example, a task might be forthe zone player 400 to synchronize playback of audio with one or moreadditional zone players. In a fourth example, a task might be to pairthe zone player 400 with one or more zone players to create amulti-channel audio environment. In a fifth example, a task might be toshape the sound output from zone player 400 based on an orientation ofzone player 400, a different zone player, or a group of zone playersincluding zone player 400. Other tasks, such as those described herein,may be achieved via the one or more software modules 414 and theprocessor 408.

The audio processing component 412 may include one or moredigital-to-analog converters (DAC), an audio preprocessing component, anaudio enhancement component or a digital signal processor, and so on. Incertain embodiments, the audio that is retrieved via the networkinterface 402 is processed and/or intentionally altered by the audioprocessing component 210. Further, the audio processing component 412may produce analog audio signals. The processed analog audio signals arethen provided to the audio amplifier 416 for play back through speakers418. In addition, the audio processing component 412 may includenecessary circuitry to process analog or digital signals as inputs toplay from zone player 400, send to another zone player on a network, orboth play and send to another zone player on the network. An exampleinput includes a line-in connection (e.g., an auto-detecting 3.5 mmaudio line-in connection).

The audio amplifier 416 is a device that amplifies audio signals to alevel for driving one or more speakers 418. The one or more speakers 418may include an individual transducer (e.g., a “driver”) or a completespeaker system that includes an enclosure including one or more drivers.A particular driver may be a subwoofer (for low frequencies), amid-range driver (middle frequencies), and a tweeter (high frequencies),for example. An enclosure may be sealed or ported, for example.

A zone player 400 may also be referred to herein as a playback device.An example playback device includes a Sonos S5, which is manufactured bySonos, Inc. of Santa Barbara, Calif. The S5 is an example zone playerwith a built-in amplifier and speakers. In particular, the S5 is afive-driver speaker system that includes two tweeters, two mid-rangedrivers, and one subwoofer. When playing audio content via the S5, theleft audio data of a track is sent out of the left tweeter and leftmid-range driver, the right audio data of a track is sent out of theright tweeter and the right mid-range driver, and mono bass is sent outof the subwoofer. Further, both mid-range drivers and both tweeters havethe same equalization (or substantially the same equalization). That is,they are both sent the same frequencies, just from different channels ofaudio. Audio from Internet radio stations, online music and videoservices, downloaded music, analog audio inputs, television, DVD, and soon may be played from a Sonos S5. While the S5 is an example of a zoneplayer with speakers, it is understood that a zone player with speakersis not limited to one with a certain number of speakers (e.g., fivespeakers as in the S5), but rather can contain one or more speakers.Further, a zone player may be part of another device, which might evenserve a purpose different than audio (e.g., a lamp).

IV. Example Controller

Referring now to FIG. 5, there is shown an example controller 500, whichmay correspond to the controlling device 130 in FIG. 1. The controller500 may be used to facilitate the control of multi-media applications,automation and others in a system. In particular, the controller 500 isconfigured to facilitate a selection of a plurality of audio sourcesavailable on the network and enable control of one or more zone players(e.g., the zone players 102 to 124 in FIG. 1) through a wireless networkinterface 508. According to one embodiment, the wireless communicationsis based on an industry standard (e.g., infrared, radio, wirelessstandards IEEE 802.11a, 802.11b 802.11g, 802.11n, or 802.15). Further,when a particular audio is being accessed via the controller 500 orbeing played via a zone player, a picture (e.g., album art) or any otherdata, associated with the audio source may be transmitted from a zoneplayer or other electronic device to the controller 500 for display.

The controller 500 is provided with a screen 502 and an input interface514 that allows a user to interact with the controller 500, for example,to navigate a playlist of many multimedia items and to controloperations of one or more zone players. The screen 502 on the controller500 may be a Liquid Crystal Display (LCD) screen, for example. Thescreen 500 communicates with and is commanded by a screen driver 504that is controlled by a microcontroller (e.g., a processor) 506. Thememory 510 may be loaded with one or more application modules 512 thatcan be executed by the microcontroller 506 with or without a user inputvia the user interface 514 to achieve certain tasks. In one example, anapplication module 512 is configured to facilitate grouping a number ofselected zone players into a zone group and synchronizing the zoneplayers for audio play back. In another example, an application module512 is configured to control the audio sounds (e.g., volume) of the zoneplayers in a zone group. In operation, when the microcontroller 506executes one or more of the application modules 512, the screen driver504 generates control signals to drive the screen 502 to display anapplication specific user interface accordingly.

The controller 500 includes a network interface 508 that facilitateswireless communication with a zone player. In one embodiment, thecommands such as volume control and audio playback synchronization aresent via the network interface 508. In another embodiment, a saved zonegroup configuration is transmitted between a zone player and acontroller via the network interface 508. The controller 500 may controlone or more zone players, such as 102 to 124 of FIG. 1. There may bemore than one controller for a particular system. Further, a controllermay be integrated into a zone player.

It should be noted that other network-enabled devices such as aniPhone™, iPad™ or any other smart phone or network-enabled device (e.g.,a networked computer such as a PC or Mac may also be used as acontroller) may be used as a controller to interact or control zoneplayers in a particular environment. According to one embodiment, asoftware application or upgrade may be downloaded onto a network enableddevice to perform the functions described herein.

In certain embodiments, a user may create a zone group including atleast two zone players from the controller 500. The zone players in thezone group may play audio in a synchronized fashion, such that all ofthe zone players in the zone group play back an identical audio sourceor a list of identical audio sources in a synchronized manner such thatno (or substantially no) audible delays or hiccups could be heard.Similarly, in one embodiment, when a user increases the audio volume ofthe group from the controller 500, the signals or data of increasing theaudio volume for the group are sent to one of the zone players andcauses other zone players in the group to be increased together involume.

A user via the controller 500 may group zone players into a zone groupby activating a “Link Zones” or “Add Zone” soft button, or de-grouping azone group by activating an “Unlink Zones” or “Drop Zone” button. Forexample, one mechanism for ‘joining’ zone players together for audioplay back is to link a number of zone players together to form a group.To link a number of zone players together, a user may manually link eachzone player or room one after the other. For example, assume that thereis a multi-zone system that includes the following zones: Bathroom,Bedroom, Den, Dining Room, Family Room, and Foyer. A user may use atouchscreen, pointing device (e.g., a mouse, trackball, and so on),gesture-based interaction, or combination of any of these techniques todrag and drop zones to configure a zone group, including adding orremoving one or more zones or zone players from a zone group.

In certain embodiments, a user can link any number of the six zoneplayers, for example, by starting with a single zone and then manuallylinking each zone to that zone.

In certain embodiments, a set of zones can be dynamically linkedtogether using a command to create a zone scene or theme (subsequent tofirst creating the zone scene). For instance, a “Morning” zone scenecommand may link the Bedroom, Office, and Kitchen zones together in oneaction. Without this single command, the user would need to manually andindividually link each zone. The single command might include a mouseclick, a double mouse click, a button press, a gesture, or some otherprogrammed action. Other kinds of zone scenes may be programmed.

In certain embodiments, a zone scene may be triggered based on time(e.g., an alarm clock function). For instance, a zone scene may be setto apply at 8:00 am. The system can link appropriate zonesautomatically, set specific music to play, and then stop the music aftera defined duration. Although any particular zone may be triggered to an“On” or “Off” state based on time, for example, a zone scene enables anyzone(s) linked to the scene to play a predefined audio (e.g., afavorable song, a predefined playlist) at a specific time and/or for aspecific duration. If, for any reason, the scheduled music failed to beplayed (e.g., an empty playlist, no connection to a share, failedUniversal Plug and Play (UPnP), no Internet connection for an InternetRadio station, and so on), a backup buzzer may be programmed to sound.The buzzer may include a sound file that is stored in a zone player, forexample.

V. Shaping Sound Based on Orientation

In certain embodiments, an audio data stream is obtained by a playbackdevice having one or more speaker drivers (or the playback device iscoupled to one or more speaker drivers, or the playback device includesone or more speaker drivers and is coupled to one or more speakerdrivers), an orientation of the playback device, and in particular thespeaker arrangement, is determined, and sound is reproduced by theplayback device based on the orientation.

FIG. 6A shows an illustration of an example zone player 600 having abuilt-in amplifier and speakers 602. The zone player 600 is shown in afirst orientation. For sake of discussion, the first orientation may bereferred to herein as the “horizontal orientation,” though any name maybe given to the orientation of the zone player 600 shown in FIG. 6A.

FIG. 6B shows an illustration of the example zone player 600 in a secondorientation that is different from the first orientation. For sake ofdiscussion, the second orientation may be referred to herein as the“vertical orientation,” though any name may be given to the orientationof the zone player 600 shown in FIG. 6B.

Based on the orientation of the zone player 600, the sound reproduced bythe zone player 600 may be shaped differently. For example, the soundcoming from each speaker driver may be configured to reproduce adifferent frequency range, channel, or both frequency range and channeldepending on the orientation. In another example, the sound coming froma plurality of speakers 602 in the zone player 600 may be in stereo whenin horizontal position, whereas the sound coming from the same pluralityof speakers 602 may be in monaural when in vertical position. Thisallows increased optimization of the sound coming from the zone player600. Further, this allows customization of the sound coming from thezone player 600.

In a first example embodiment, a stereophonic signal is reproduced by aplurality of speakers based on a first orientation, and a monauralsignal is reproduced by the plurality of speakers based on a secondorientation. Using the zone player 600 shown in FIGS. 6A and 6B toillustrate, a stereophonic signal may be reproduced by the zone playerin the horizontal orientation. That is, the left channel audio may berouted to the left speaker 604 and the right channel audio may be routedto the right speaker 606. A monaural signal may be routed to the tweeter608. When the zone player 600 is rotated, and in particular rotated to a90 degree angle (that is, the vertical orientation), from its previousorientation, the sound characteristics may change. For example, amonaural signal is played out of both the left and right speakers 604and 606, instead of a stereophonic sound.

In a second example embodiment, a speaker driver reproduces a monauralsignal and either a right or left channel signal based on a firstorientation, and the speaker driver reproduces only a monaural signalbased on a second orientation. Again, using the zone player 600 toillustrate, in the horizontal orientation, the left speaker 604 may playthe left channel audio above a threshold frequency (e.g., above 200 Hz)and a monaural signal below the threshold frequency; likewise, the rightspeaker 606 may play the right channel audio above a threshold frequencyand a monaural signal below the threshold frequency. In the verticalorientation, the left and right speakers 604 and 606 may play a monauralsignal and not play separate left and right channels. The tweeter 608may play a monaural signal in both orientations, but the frequency rangemay be altered based on the orientation.

In a third example embodiment, a speaker driver reproduces a first rangeof frequencies based on a first orientation, and the speaker driverreproduces a second range of frequencies based on a second orientation.Using the tweeter 608 to illustrate, in the horizontal orientation, thetweeter 608 might reproduce frequencies above 7.5 kHz, and in thevertical orientation the tweeter 608 might reproduce frequencies above 3kHz. As the frequency response changes for the tweeter 608, the soundfrom the left and right speakers 604 and 608 might also adjust so thatthe frequency range is accounted for across the listening range.

In a fourth example embodiment, the playback device does not contain adisplay. Thus, in some embodiments, the playback device does contain adisplay; examples of such playback devices might include a television, atablet computer (e.g., an Apple, Inc. iPad™ or a Microsoft Windows™based tablet), or a smart phone or device (e.g., Apple, Inc. iPhone™ oriTouch™). In a fifth example embodiment, the playback device is anaudio-only device, such as a loudspeaker system. The zone player 600 isan example playback device that does not contain a display and is anaudio-only device.

In addition, it is understood that a speaker arrangement may beconnected to a zone player, but physically separate from each other(e.g., such as shown in FIGS. 2B and 2C). Even with such an arrangement,the sound coming from the speaker arrangement may be shaped based on itsorientation. As such, the embodiments described herein with respect tosound shaping are not limited to a playback device with built-inspeakers.

In certain embodiments, sound is reproduced by a playback device basedon an orientation of the playback device and whether the playback deviceis paired with another playback device. In some instances, theorientation may be configured to trump the pairing, and the sound isreproduced based on the orientation. In some instances, the pairing maybe configured to trump the orientation, and the sound is reproducedbased on the pairing. In some instances, both the orientation and thepairing determine the sound reproduction. In some embodiments, the soundmay be reproduced based on orientation and any of: pairing, grouping,and consolidation of playback devices.

Using the zone player 600 shown in FIG. 6A to provide an illustration, astereophonic signal may be reproduced by the zone player 600 in thehorizontal orientation. If the zone player 600 is paired to another zoneplayer, for example, then the zone player 600 will determine that it ispaired and horizontal, which will alter the sound coming from the zoneplayer 600. Particularly, if the zone player 600 is the left speaker ina stereo pair, for example, then the left channel audio will be playedfrom the zone player 600. The left speaker 604 may handle one set offrequencies and the right speaker 606 may handle another set offrequencies.

In certain embodiments, sound is reproduced by a playback device basedon an orientation of a different playback device. For example, playbackdevice A and playback device B might be paired, such that the twoplayback devices reproduce a certain overall sound. In some instances,the sound from playback A may be based on the orientation of playbackdevice B. In some instances, the sound from playback B may be based onthe orientation of the playback device A. In some instances, the overallsound may be based on the orientation of both playback devices A and B.

Referring back to FIG. 1, the family room shows two zone players 106 and108. The zone players 106 and 108 may be configured to respond to eachother's orientation. For example, the sound coming from the zone player106 may be based on the orientation of the zone player 108. Similarly,the sound coming from the zone player 108 may be based on theorientation of the zone player 106. As such, the sound coming from bothzone players 106 and 108 may be customizable.

In certain embodiments, an audio data stream is obtained by a playbackdevice having one or more speaker drivers, an orientation of theplayback device is determined, and sound is reproduced by the playbackdevice based on the orientation. In some embodiments, the audio datastream is modified by the playback device based on the orientation. Insome embodiments, the audio data stream is modified prior to beingobtained by the playback device, yet the modification is based on theorientation.

In certain embodiments, a playback device contains one or more speakerdrivers that face a particular direction. In some instances, anorientation of the playback device is based on a rotation about an axisthat is perpendicular to the front face. That is, the one or morespeaker drivers still face the particular direction regardless of therotation. An illustration of this type of rotation is shown in FIGS. 6Aand 6B.

In certain embodiments, one or more speaker drivers may be turned on andoff automatically based on device orientation. A speaker driver may beturned off by electronically switching off the driver, or alternatively,by muting the speaker driver such that the driver is effectively turnedoff.

In certain embodiments, a playback device may have only one speakerdriver with characteristics affected based on the orientation of thedevice.

In certain embodiments, sound shaping for reproduction and associatedspeaker driver configuration may be provided via a change or upgrade tosoftware associated with the playback device. In one example, a playbackdevice might not include an accelerometer or a similar type of hardwaredevice to automatically determine its orientation, but the playbackdevice may be configured in software to shape its sound based on anorientation input through a controller (or some other input mechanism,such as a button on the playback device itself). This is particularlyuseful for a playback device that is capable of receiving a softwareupgrade (though, it is understood that a new playback device may notrequire a software upgrade, but still may benefit from this technology)and has at least some capability of shaping its sound, but does notinclude an accelerometer or hardware to automatically compute anorientation. As such, a software upgrade can change the hardwarefunctionality of the playback device by enabling sound shapingresponsive to a speaker orientation.

In certain embodiments, the orientation is determined via anaccelerometer or some other hardware device. In certain embodiments, theorientation is determined based on a user input via a controller or someother input mechanism, such as a button on the playback device itself.This is useful for new playback devices (or existing playback devicesthat are capable of receiving software upgrades to shape sound) that donot contain an accelerometer or similar hardware to provide anorientation reading. In certain embodiments, the orientation may bedetermined by the playback device either by analyzing an accelerometerreading or receiving a user input. In certain embodiments, an indicator(on the user interface of the controller and/or playback device, forexample) may display the playback device's orientation to the user. Theindicator may include a light, textual display, graphic, or any othersign that provides an indication to the user of the playback device'sorientation.

For example, a playback device may not originally include an ability tomodify its configuration based on orientation, but a software upgrademay add that capability to the device. In certain embodiments,frequencies played through the playback device may be changed based onthe orientation, zone group, or both the orientation and zone group ofanother playback device.

In certain embodiments, a playback device may include an accelerometeror other sensor or mechanism to identify an orientation but only providebasic shaping of sound. A software update or upgrade may be provided tothe playback device to improve sound shaping capabilities of the device.

In some instances, an orientation of the playback device is based on arotation about an axis that is parallel to the front face (or a surfacedesignated as the “front face”). An illustration of this type ofrotation is shown in FIGS. 7A and 7B. As such, upon a rotation, the oneor more speaker drivers may face a direction that is different from theparticular direction. In FIG. 7A, the zone player 700 is generally aimedtoward the listener. Upon rotation, as shown in FIG. 7B, the zone player700 is now generally aimed away from the listener. It is understood thatadditional speaker drivers may be incorporated into the zone player 700,such that at least one speaker driver always faces the listenerregardless of rotation. Then, certain frequencies may be routed tospeakers that face the listener (directional frequencies) and certainfrequencies may be routed to speakers that do not face the listener(non-directional frequencies).

In some instances, an orientation of a playback device is based on arotation about more than one axis. That is, a playback device may berotated about two or more axes. The sound output from the playbackdevice or another playback device may be based on the particularrotation.

FIG. 8 shows an example functional block diagram of a zone player 802 inaccordance with an embodiment. The functional block diagram in FIG. 8 issimilar to the functional block diagram of the zone player 400 of FIG.4, and further includes a sensor module 800. As such, many of thereference numerals are shared between figures.

In certain embodiments, the sensor module 802 includes an accelerometerto detect how the zone player 800, and in particular, how the speakerdriver(s) are oriented. In certain embodiments, the accelerometer deviceis a three axes accelerometer. Based on the orientation, the soundoutput from the zone player 800 or another zone player(s), whose soundmay depend on the orientation of the zone player 800, may be shaped.

In certain embodiments, other types of sensors may be employed to detectposition and orientation of the zone player 800. For example, a sensormay be used to determine speaker position relative to any of: a floor,wall, and ceiling. This information may be used to, for example,determine the speaker height relative to a listener in a room or thespeaker distance from a wall or corner, and based on that information,an audio characteristic of one or more playback devices may bedetermined. For example, an audio characteristic of one playback devicemight be determined, or an audio characteristic for any of a number ofdifferent playback devices within a local area may be determined tobetter optimize the sound environment based on the orientation.

FIG. 9 depicts an example flow diagram representative of process(es)that may be implemented using, for example, computer readableinstructions that may be used to process an audio signal based on anorientation of a zone player and/or other playback device. The exampleprocess(es) of FIG. 9 may be performed using a processor, a controllerand/or any other suitable processing device. For example, the exampleprocess(es) of FIG. 9 may be implemented using coded instructions (e.g.,computer readable instructions) stored on a tangible computer readablemedium such as a flash memory, a read-only memory (ROM), and/or arandom-access memory (RAM). As used herein, the term tangible computerreadable medium is expressly defined to include any type of computerreadable storage and to exclude propagating signals. Additionally oralternatively, the example process(es) of FIG. 9 may be implementedusing coded instructions (e.g., computer readable instructions) storedon a non-transitory computer readable medium such as a flash memory, aread-only memory (ROM), a random-access memory (RAM), a cache, or anyother storage media in which information is stored for any duration(e.g., for extended time periods, permanently, brief instances, fortemporarily buffering, and/or for caching of the information). As usedherein, the term non-transitory computer readable medium is expresslydefined to include any type of computer readable medium and to excludepropagating signals.

Alternatively, some or all of the example process(es) of FIG. 9 may beimplemented using any combination(s) of application specific integratedcircuit(s) (ASIC(s)), programmable logic device(s) (PLD(s)), fieldprogrammable logic device(s) (FPLD(s)), discrete logic, hardware,firmware, and so on. Also, some or all of the example process(es) ofFIG. 9 may be implemented manually or as any combination(s) of any ofthe foregoing techniques, for example, any combination of firmware,software, discrete logic and/or hardware. Further, although the exampleprocess(es) of FIG. 9 are described with reference to the flow diagramof FIG. 9, other methods of implementing the process(es) of FIG. 9 maybe employed. For example, the order of execution of the blocks may bechanged, and/or some of the blocks described may be changed, eliminated,sub-divided, or combined. Additionally, any or all of the exampleprocess(es) of FIG. 9 may be performed sequentially and/or in parallelby, for example, separate processing threads, processors, devices,discrete logic, circuits, and so on.

FIG. 9 shows a flowchart that illustrates an example method 900 forprocessing an audio signal based on an orientation of a zone player. Themethod 900 may be iteratively performed to accommodate a change inorientation. Further, although the method 900 is described about arotation of a zone player detected by a sensor module 800, it isunderstood that the method 900 is equally applicable should the rotationbe manually entered, or a height or other physical offset be provided.The method 900 may be understood in conjunction with the zone player ofFIG. 8, and therefore, the description references FIG. 8 to facilitateeasy understanding of the example method embodiment.

The method 900 starts at block 902 by determining an orientation of thezone player 400. Block 902 might be triggered when the zone player 400is turned on, when the zone player 400 is ready to play audio, when aparticular time interval expires, or upon some other programmed triggerpoint. Irrespective of the trigger point, the sensor module 800 isactivated to detect the orientation of the zone player 400, and inparticular, to detect the orientation of the speaker array that providesthe sound. Depending on implementation, the sensor module 800 may outputa sensor signal or a set of sensor signals. The sensor signal(s) may beprovided to the processor 408, which is configured to determine theorientation based on the signal(s), and provides the orientation data tothe audio processing component 412 to process the audio.

According to certain embodiments, when the audio is processed upstreamfrom the zone player 400 based on the orientation of the zone player 400or when the orientation of the zone player 400 is important to otherconnected zone players for group audio shaping, then the processor 408may provide the orientation data from block 902 to another device orzone player via the network interface 402. In some embodiments, such aswhen the audio is processed upstream from the zone player 400, the audioprocessing component 412 may not need to provide any additional audioprocessing based on the orientation.

At block 904, the audio is configured and routed to the appropriatespeaker based on the orientation. In some embodiments, the audio isconfigured by the zone player 400, itself, via the audio processingcomponent 412, for example. In some embodiments, the audio is configuredupstream from the zone player 400. The configured audio may then be sentto the zone player 400 for play. In some embodiments, the audio isconfigured and routed based on at least two states of the zone player400: orientation and whether the zone player is paired, grouped, orconsolidated with one or more additional zone players. At block 906, theaudio is played from one or more zone players.

VI. Orientation-Based Equalization

In certain embodiments, an orientation sensor is used to providedifferent equalization (EQ) settings based on a detected orientation ofa playback device in which the orientation sensor is positioned. Forexample, the playback device may have a vertical orientation, ahorizontal orientation, or another angular orientation. The playbackdevice may not be lying completely flat, for example, and may instead bepositioned at a slight angle that should be treated as a horizontal orvertical orientation. A horizontal orientation and a verticalorientation are each associated with a different baseline for EQsettings for output of the playback device.

An orientation sensor, such as an accelerometer (e.g., a FreescaleMMA7660 accelerometer and so on), may be used to determine anorientation of the playback device in the presence of environmentalconditions, such as acoustic noise, and with respect to a playbackdevice that is subject to a variation in tolerance based on at least oneof temperature variation and manufacturing variation. For example, theorientation sensor is to provide an orientation determination in thepresence of acoustic noise and vibration, as well as temperature.

In certain embodiments, different equalizer and stereo setting areapplied depending upon an orientation of the playback device. Forexample, while operating in a non-stereo pair environment, a verticalunit provides sound in mono but a horizontal unit provides sound instereo. In operation, the orientation sensor works with a processingalgorithm to provide an orientation value to an equalizer.

In certain examples, pitch, roll, and yaw may be used to define anorientation. Roll pitch angles may be measured in reference to the“plane” of a front grille of the playback device (e.g., referenced tothe plane formed by tangents at a center of the grille). For example,“interesting” positions in a wall mount are present when a front surfaceof the unit is most visible to the user and, thus, is likely toinfluence the angles at which the playback device is placed.

In certain examples, an accelerometer is mounted in a playback devicesuch that axes of the accelerometer are either aligned with the grilleplane or are orthogonal to the grille plan. In an example, when theplayback device is positioned on a table top, the pitch angles (forpurposes of example illustration only) are −5.5 degrees for a horizontalposition and −13 degrees for a vertical position.

In certain examples, hysteresis (e.g. between two valid orientations)and resolution to a specific orientation may be applied to determine anorientation. In an orientation sensing state-machine, vertical is thedefault state in the event that the orientation cannot be determined.Thus, if a playback device is powered up or rebooted such that theactual orientation cannot be determined, a vertical orientation isreported. For ease of implementation, an entire unknown “region” (as afunction of pitch and roll) is implemented as the region of hysteresis.This provides for an orientation determination state machine as shown inFIG. 10.

In the example of FIG. 10, a condition “V” represents conditions (e.g.,roll, pitch) for which the accelerometer, together with a detectionalgorithm, renders a vertical orientation. Condition “H” representsconditions for which a horizontal orientation is rendered. Theconditions of roll and pitch for which V is true and for which H is trueshould be non-overlapping. Under conditions for which either V or H ismarginally true, the orientation should not revert to the other state.That is, if a unit is “rolled” from a horizontal orientation until theaccelerometer registers a vertical orientation, the unit should notsubsequently register a horizontal orientation under temperature changesor playing content.

In certain examples, the accelerometer may be affected by variablesaffecting tolerance. As a result, roll, pitch combinations that yield adefinitive horizontal orientation or vertical orientation in view oftolerance concerns and operating temperature variances are limited.

FIG. 11 shows four regions of orientation determination based on areference horizontal orientation. The graph of FIG. 11 shows thepossible response of orientation sensing to most combinations of pitchand roll relative to the reference horizontal orientation (e.g., grilleplane vertical and long edge of grille horizontal). FIG. 11 illustratesfour areas defined for particular orientations. The example diagram 1100depicts a first area 1110, in which an orientation sensor shouldindicate a horizontal orientation for the associated angles of pitch androll. A second area 1120 indicates selected angles of pitch and roll forwhich a vertical orientation should be returned by the orientationsensor. For angles of pitch and roll illustrates in a third area 1130,the orientation sensor may return a horizontal orientation. A fourtharea 1140 indicates angles of pitch and roll for which the orientationsensor may return a vertical or unknown orientation, but not ahorizontal orientation.

FIG. 12 illustrates an example unknown orientation region produced byvarying combinations of roll and pitch. The example of FIG. 12 shows aplot 1200 of smallest (e.g., due to tolerance stackup) roll, pitchcombination for which a horizontal orientation is definitive. Thesmallest roll, pitch combination is indicated by line 1210. That is, fora given pitch angle, all roll angles under the dataline 1210 provide ahorizontal orientation determination. The tolerance stackup alsoprovides a correspondingly largest combination of roll, pitch whichyields a vertical orientation. The largest combination of roll and pitchto yield a vertical orientation is indicated by line 1220. For a givenpitch angle, a roll value that is above the line 1220 yield a verticalorientation. The gap between the two lines 1210, 1220 represents ahysteresis for this tolerance stackup.

In certain examples, in order to help ensure that orientation sensing isnot adversely affected by acoustic vibration (e.g., through inducingmechanical stress which manifests as additional acceleration beyond thatproduced by gravity), filtering is provided on the raw accelerationvalues. The filtering leads to an increase in response time to anorientation change. Additionally, in certain examples, in order to helpreduce or prevent frequent orientation changes in the presence of severenoise (e.g., poor wall mount), orientation changes may be limited to acertain period of time (e.g., limiting orientation changes to one everythirty seconds).

In certain examples, an algorithm may be used to determine a desiredorientation indication (horizontal or vertical) in all reasonableorientations involving forward and back pitch. For example, a playbackdevice having a warped cabinet may introduce vibration and falseorientation changes that should be prevented using the accelerometer. Asdisclosed above, the accelerometer is mounted in the playback devicesuch that, in a horizontal orientation, the Z-axis of the accelerometeris virtually vertical. The Y-axis runs from front-to-back of theaccelerometer, while the X-axis runs from left to right of theaccelerometer. The axes of the example accelerometer are shown with aline-drawing representation in a vertical table top position in FIG. 13.

In certain examples, electronics may be provided via one or more printedcircuit boards (PCBs) mounted on one or more mounting surface(s) of aplayback device. However, in an example, one or more printed circuitboards (PCBs) are not mounted parallel (or orthogonal) to the mountingsurface(s) of the playback device, but, rather, are canted 5.5 degreesto the horizontal in the case of a horizontal orientation and 13 degreesto the horizontal in the case of a vertical orientation.

An offset may be introduced based on a canted or offset orientation ofthe playback device. Additionally, vibration and system non-linearitymay introduce an offset, such as a direct current (DC) offset. Anexample method used to remove the effect of such a DC offset applies arule to the review of each sample taken:G=√(Xg ² +Yg ² +Zg ²)  (Equation 1),wherein G represents a gravity vector and X, Y, and Z represent threeaxes. That is, for any one sample of the three axes, a resulting gravityvector equals a single G. Applying Equation 1 can help reduce or removeoffset vectors.

By accounting for audio noise and DC offset, the playback device mayprocess available data and make orientation changes based on a user'sdesired pitch. Pitch is the horizontal axis across the surface of thegrille independent of the orientation. Pitch becomes a factor when aplayback device is used outside of a normal table top orientation.Examples include horizontal or vertical wall mounts where a unit ismounted above or below an average listening height, suggesting a forwardpitch (e.g., angling downward) or backward pitch (e.g., angling upward).In certain examples, an increased pitch reduces an ability of theplayback device to resolve an orientation.

In certain examples, experimental data may be used to determine minimumand maximum ranges for each axis (e.g., X, Y, Z). A line 1410illustrates a horizontal resolution from a vertical position based onroll angle and pitch angle. A line 1420 illustrates a horizontalresolution from a change in vertical position based on roll angle andpitch angle. As illustrated, for example, in FIG. 14, as pitch increases(e.g., moving horizontally left and right in the graph of FIG. 14), apoint is approached at which the roll angle (e.g., moving from ahorizontal to vertical orientation) may no longer produce an orientationanswer.

In certain examples, an X axis 1510, Y axis 1520, and Z axis 1530 may bedefined with respect to a playback device 1540 as shown in FIG. 15.Using x, y, and z, the following may be applied to make an orientationdecision. For a transition into a vertical orientation:|x|>|z|+m+n(1−|y|)  (Equation 2).

For a transition into a horizontal orientation:|z|>|x|+m+n(1−|y|)  (Equation 3).

In Equations 2 and 3, them term defines a general hysteresis and noiselevel that would, even in extreme pitch values (e.g., a y very close to1), still allow a reliable transition or help prevent an unreliabletransition. The n term is used to provide a more usable hysteresismoving between orientations that are more the norm (e.g., very small yvalues with no added pitch).

Equations 2 and 3 may be used with Euler angles to express anglesdescribing orientation graphically. Using Euler angles, a final relativeorientation of an object moved in three dimensions may be solved bysolving three unit rotations around a defined axis, for example. Eulerangles may be used to represent a spatial orientation of the object as acomposition of rotations from a frame of reference (e.g., a coordinatesystem). In the following, the fixed system is denoted in lower case (x,y, z) and the rotated system is denoted in upper case letters (X, Y, Z).

Given a reference frame and an object or other frame for which anorientation is to be described, a line of nodes (N) is defined as anintersection of the xy and the XY coordinate planes (e.g., a line ofnodes is a line perpendicular to both the z and Z axis). Then, its Eulerangles may be defined as:

-   -   α (or) is the angle between the x-axis and the line of nodes.    -   β (or θ) is the angle between the z-axis and the Z-axis.    -   γ (or ψ) is the angle between the line of nodes and the X-axis.

In our case we are applying this method to find limits to a roll anglegiven an existing pitch angle. This is the result of the product of twoEuler angle matrices:

$\begin{matrix}{D = \left\lbrack {\cos({phi})} \right.} & {\sin({phi})} & \left. 0 \right\rbrack \\{\left\lbrack {- {\sin({phi})}} \right.} & {\cos({phi})} & \left. 0 \right\rbrack \\{\left\lbrack 0 \right.} & {0} & \left. 1 \right\rbrack\end{matrix}$ $\begin{matrix}{C = \left\lbrack 1 \right.} & {0} & \left. 0 \right\rbrack \\{\left\lbrack 0 \right.} & {\cos({theta})} & \left. {\sin({theta})} \right\rbrack \\{\left\lbrack 0 \right.} & {- {\sin({theta})}} & {\cos({theta}\rbrack}\end{matrix}$ $\begin{matrix}{{C^{*}D} = \left\lbrack {\cos({phi})} \right.} & {\sin({phi})} & \left. 0 \right\rbrack \\{\left\lbrack {{- {\cos({theta})}}{\sin({phi})}} \right.} & {{\cos({theta})}{\cos({phi})}} & \left. {\sin({theta})} \right\rbrack \\{\left\lbrack {{\sin({theta})}{\sin({phi})}} \right.} & {{- {\sin({theta})}}{\cos({phi})}} & \left. {\cos({theta})} \right\rbrack\end{matrix}$solving for an angular velocity where phi=pitch (rotation around z axis)and theta=roll (rotation around y axis).

To transfer into a vertical orientation, the following equation may beused:Theta>a sin((n+m−n sin(phi))/(sqrt(2)cos(phi)))  (Equation 4).Using Equation 4 results in a usable range depicted in FIG. 16. Asillustrated in FIG. 16, varying roll and pitch angles may be used todetermine whether a playback device has a horizontal 1610 or vertical1620 orientation. Analyzing a pitch angle between −75 and 75, a verticalmode may be found for a roll angle between zero (0) and thirty-five (35)degrees, for example. A horizontal mode may be found for a roll anglebetween fifty-five (55) and ninety (90) degrees, for example.

VII. Decentralized Synchrony Groups

In certain embodiments, one or more playback devices operate in adecentralized network to facilitate one or more synchrony groups withone or more interchangeable master-slave relationships. Using adecentralized network, communication, and control model, a playbackdevice may provide content to another playback device even if the firstplayback device is not outputting that content for a listener.Additionally, a playback device may serve as a master device or controlat one point in time and may receive instructions (e.g., content and/orsynchronization) from another device serving as a master device atanother point in time.

FIG. 17 depicts an illustrative network audio system 10 operating inaccordance with a decentralized communication, organization, and controlstructure. With reference to the example of FIG. 17, the network audiosystem 10 includes a plurality of zone players 11(1) through 11(N)(generally identified by reference numeral 11(n)) interconnected by alocal network 12, all of which operate under control of one or more userinterface modules generally identified by reference numeral 13. The zoneplayers 11(n) may be the same or similar to the playback device(s)described above. One or more of the zone players 11(n) may also beconnected to one or more audio information sources, which will generallybe identified herein by reference numeral 14(n)(s), and/or one or moreaudio reproduction devices, which will generally be identified byreference numeral 15(n)(r). In the reference numeral 14(n)(s), index “n”refers to the index “n” of the zone player 11(n) to which the audioinformation source is connected, and the index “s” (s=1, . . . , Sn)refers to the “s-th” audio information source connected to that “n-th”zone player 11(n). Thus, if, for example, a zone player 11(n) isconnected to four audio information sources 14(n)(1) through 14(n)(4),the audio information sources may be generally identified by referencenumeral 14(n)(s), with Sn=4. It will be appreciated that the number ofaudio information sources Sn may vary among the various zone players11(n), and some zone players may not have any audio information sourcesconnected thereto.

Similarly, in the reference numeral 15(n)(r), index “n” refers to theindex “n” of the zone player 11(n) to which the audio reproductiondevice is connected, and the index “r” (r=1, . . . , Rn) refers to the“r-th” audio information source connected to that “n-th” zone player11(n). In addition to the audio information sources 14(n)(s), thenetwork audio system 10 may include one or more audio informationsources 16(1) through 16(M) connected through appropriate networkinterface devices (not separately shown) to the local network 12.Furthermore, the local network 12 may include one or more networkinterface devices (also not separately shown) that are configured toconnect the local network 12 to other networks, including a wide areanetwork such as the Internet, the public switched telephony network(PSTN) or other networks, over which connections to audio informationsources may be established.

The zone players 11(n) associated with system 10 may be distributedthroughout an establishment such as residence, an office complex, ahotel, a conference hall, an amphitheater or auditorium, or other typesof establishments. For example, if the zone players 11(n) and theirassociated audio information source(s) and/or audio reproductiondevice(s) are distributed throughout a residence, one may be located ina living room, another may be located in a kitchen, another may belocated in a dining room, and yet others may be located in respectivebedrooms, to selectively provide entertainment in those rooms. Incertain examples, a place of application of the zone players 11(n) isnot important, and the zone players 11(n) may be used in a variety oflocations or environments including buildings, vehicles, outdoors, etc.

On the other hand, if the zone players 11(n) and their associated audioinformation source(s) and/or audio reproduction device(s) aredistributed throughout an office complex, one may, for example, beprovided in each office to selectively provide entertainment to theemployees in the respective offices. Similarly, if the zone players11(n) and associated audio information source(s) and/or audioreproduction device(s) are used in a hotel, they may be distributedthroughout the rooms to provide entertainment to the guests. Similararrangements may be used with zone players 11(n) and associated audioinformation source(s) and/or audio reproduction device(s) used in anamphitheater or auditorium. Other arrangements in other types ofenvironments will be apparent to those skilled in the art. In each case,the zone players 11(n) may be used to selectively provide entertainmentin the respective locations, for example.

The audio information sources 14(n)(s) and 16(m) may be any of a numberof types of conventional sources of audio information, including, forexample, compact disc (“CD”) players, AM and/or FM radio receivers,analog or digital tape cassette players, analog record turntables, andthe like. In addition, the audio information sources 14(n)(s) and 16(m)may comprise digital audio files stored locally on, for example,personal computers (PCs), personal digital assistants (PDAs), or similardevices capable of storing digital information in volatile ornon-volatile form. As noted above, the local network 12 may also have aninterface to a wide area network, over which the network audio system 10may obtain audio information. Moreover, one or more of the audioinformation sources 14(n)(s) may also include an interface to a widearea network such as the Internet, the public switched telephony network(PSTN), or any other source of audio information. In addition, one ormore of the audio information sources 14(n)(s) and 16(m) may includeinterfaces to radio services delivered over, for example, satellite.Audio information obtained over the wide area network may include, forexample, streaming digital audio information such as Internet radio,digital audio files stored on servers, and other types of audioinformation and sources.

Generally, the audio information sources 14(n)(s) and 16(m) provideaudio information associated with audio programs to the zone players forplayback. A zone player that receives audio information from an audioinformation source 14(n)(s) that is connected thereto may provideplayback and/or forward the audio information, along with playbacktiming information, over the local network 12 to other zone players forplayback. Similarly, each audio information source 16(m) that is notdirectly connected to a zone player may transmit audio information overthe network 12 to any zone player 11(n) for playback.

In addition, the respective zone player 11(n) may transmit the audioinformation that it receives either from an audio information source14(n)(s) connected thereto, or from an audio information source 16(m),to selected ones of the other zone players 11(n′), 11(n″), . . . (n notequal to n′, n″, . . . ) for playback by those other zone players. Theother zone players 11(n′), 11(n″), . . . to which the zone player 11(n)transmits the audio information for playback may be selected by a userusing the user interface module 13. In that operation, the zone player11(n) transmits the audio information to the selected zone players11(n′), 11(n″), . . . over the network 12. The zone players 11(n),11(n′), 11(n″), . . . operate such that the zone players 11(n′), 11(n″),. . . synchronize their playback of the audio program with the playbackby the zone player 11(n), so that the zone players 11(n), 11(n′), 11(n″)provide the same audio program at the same time.

Users, using user interface module 13, may also enable differentgroupings or sets of zone players to provide audio playback of differentaudio programs synchronously. For example, a user, using a userinterface module 13, may enable zone players 11(1) and 11(2) to play oneaudio program, audio information for which may be provided by, forexample, one audio information source 14(1)(1). The same or a differentuser may, using the same or a different user interface module 13, enablezone players 11(4) and 11(5) to contemporaneously play another audioprogram, audio information for which may be provided by a second audioinformation source, such as audio information source 14(5)(2). Further,a user may enable zone player 11(3) to contemporaneously play yetanother audio program, audio information for which may be provided byyet another audio information source, such as audio information source16(1). As yet another possibility, a user may contemporaneously enablezone player 11(1) to provide audio information from an audio informationsource connected thereto, such as audio information source 14(1)(2), toanother zone player, such as zone player 11(6) for playback.

In the following, the term “synchrony group” is used to refer to a setof one or more zone players that are to play the same audio programsynchronously. Thus, in the above example, zone players 11(1) and 11(2)comprise one synchrony group, zone player 11(3) comprises a secondsynchrony group, zone players 11(4) and 11(5) comprise a third synchronygroup, and zone player 11(6) comprises yet a fourth synchrony group.Thus, while zone players 11(1) and 11(2) are playing the same audioprogram, the zones players 11(1) and 11(2) play the audio programsynchronously. Similarly, while zone players 11(4) and 11(5) are playingthe same audio program, zone players 11(4) and 11(5) play the audioprogram synchronously. On the other hand, zone players that are playingdifferent audio programs may do so with unrelated timings. That is, forexample, the timing with which zone players 11(1) and 11(2) play theiraudio program may have no relationship to the timing with which zoneplayer 11(3), zone players 11(4) and 11(5), and zone player 11(6) playtheir audio programs. It will be appreciated that, since “synchronygroup” is used to refer to sets of zone players that are playing thesame audio program synchronously, zone player 11(1) is not part of zoneplayer 11(6)'s synchrony group, even though zone player 11(1) isproviding the audio information for the audio program to zone player11(6).

In the network audio system 10, the synchrony groups are not fixed.Users may enable them to be established and modified dynamically.Continuing with the above example, a user may enable the zone player11(1) to begin providing playback of the audio program provided theretoby audio information source 14(1)(1), and subsequently enable zoneplayer 11(2) to join the synchrony group.

Similarly, a user may enable the zone player 11(5) to begin providingplayback of the audio program provided thereto by audio informationsource 14(5)(2), and subsequently enable zone player 11(4) to join thatsynchrony group. In addition, a user may enable a zone player to leave asynchrony group and possibly join another synchrony group. For example,a user may enable the zone player 11(2) to leave the synchrony groupwith zone player 11(1), and join the synchrony group with zone player11(6). As another example, the user may enable the zone player 11(1) toleave the synchrony group with zone player 11(2) and join the synchronygroup with zone player 11(6). In connection with this example, the zoneplayer 11(1) may continue providing audio information from the audioinformation source 14(1)(1) to the zone player 11(2) for playbackthereby.

A user, using the user interface module 13, may enable a zone player11(n) that is currently not a member of a synchrony group to join asynchrony group, after which the zone player 11(n) is enabled to play anaudio program that is currently being played by that synchrony group.Similarly, a user, also using the user interface module 13, may enable azone player 11(n) that is currently a member of one synchrony group todisengage from that synchrony group and join another synchrony group,after which that zone player plays the audio program associated with theother synchrony group.

For example, if a zone player 11(6) is currently not a member of anysynchrony group, it, under control of the user interface module 13, maybecome a member of a synchrony group, after which the zone player playsthe audio program being played by the other members of the synchronygroup, in synchrony with the other members of the synchrony group. Inbecoming a member of the synchrony group, zone player 11(6) may notifythe zone player that is the master device for the synchrony group thatthe zone player wishes to become a member of its synchrony group, afterwhich that zone player also transmits audio information associated withthe audio program, as well as timing information, to the zone player11(6). As the zone player 11(6) receives the audio information and thetiming information from the master device, the zone player 11(6) playsthe audio information with the timing indicated by the timinginformation, which enables the zone player 11(6) to play the audioprogram in synchrony with the other zone player(s) in the synchronygroup.

Similarly, if a user, using the user interface module 13, enables a zoneplayer 11(n) associated with a synchrony group to disengage from thatsynchrony group, and, if the zone player 11(n) is not the master deviceof the synchrony group, the zone player 11(n) may notify the masterdevice, after which the master device may terminate transmission of theaudio information and timing information to the zone player lien). Ifthe user also enables the zone player 11(n) to begin playing anotheraudio program using audio information from an audio information source14(n)(s) connected thereto, it acquires the audio information from theaudio information source 14(n)(s) and initiate playback thereof. If theuser enables another zone player 11(n′) to join the synchrony groupassociated with zone player 11(n), operations in connection therewithmay proceed as described immediately above.

In another example, if a user, using the user interface module 13,enables a zone player 11(n) associated with a synchrony group todisengage from that synchrony group and join another synchrony group,and, if the zone player is not the master device of the synchrony groupfrom which it is disengaging, the zone player 11(n) may notify themaster device of the synchrony group from which it is disengaging, afterwhich that zone player terminates transmission of audio information andtiming information to the zone player 11(n) that is disengaging.

Contemporaneously, the zone player 11(n) may notify the master device ofthe synchrony group that it (that is, zone player 11(n)) is joining,after which the master device may begin transmission of audioinformation and timing information to that zone player 11(n). The zoneplayer 11(n) may thereafter begin playback of the audio program definedby the audio information, in accordance with the timing information sothat the zone player 11(n) plays the audio program in synchrony with themaster device.

As another example, a user, using the user interface module 13, mayenable a zone player 11(n) that is not associated with a synchronygroup, to begin playing an audio program using audio informationprovided to it by an audio information source 14(n)(s) connectedthereto. In that case, the user, also using the user interface module 13or a user interface device that is specific to the audio informationsource 14(n)(s), may enable the audio information source 14(n)(s) toprovide audio information to the zone player 11(n). After the zoneplayer 11(n) has begun playback, or contemporaneously therewith, theuser, using the user interface module 13, may enable other zone players11(n′), 11(n″), . . . to join zone player 11(n)'s synchrony group andenable that zone player (n) to transmit audio information and timinginformation thereto as described above, to facilitate synchronousplayback of the audio program by the other zone players 11(n′), 11(n″) .. . . A user may use the user interface module 13 to control otheraspects of the network audio system 10, including but not limited to theselection of the audio information source 14(n)(s) that a particularzone player 11(n) is to utilize, the volume of the audio playback, andso forth. In addition, a user may use the user interface module 13 toturn audio information source(s) 14(n)(s) on and off and to enable themto provide audio information to the respective zone players 11(n).

VIII. Conclusion

The example embodiments described herein provide for numerous ways toshape sound within an environment based on a speaker orientation. Forexample, sound may be shaped by routing frequencies and channels to aparticular speaker driver. In another example, sound may be furthershaped by taking into account other states, such as whether the zoneplayer is paired, grouped, or consolidated with one or more additionalzone players. In yet another example, sound for a whole environment froma collection of zone players may be shaped based on the orientation ofone or more of the zone players within the collection. Technology fromthe example embodiments may be used in any application where accuratelyreproduced sound is desired, such as in motorized vehicles, boats,airplanes, and in outdoor locations.

The components, elements, and/or functionality of the systems discussedabove may be implemented alone or in combination in various forms inhardware, firmware, and/or as a set of instructions in software, forexample. Certain embodiments may be provided as a set of instructionsresiding on a computer-readable medium, such as a memory, hard disk,CD-ROM, DVD, and/or EPROM, for execution on a processing device, such asa controller and/or playback device.

Various inventions have been described in sufficient detail with acertain degree of particularity. It is understood to those skilled inthe art that the present disclosure of embodiments has been made by wayof examples only and that numerous changes in the arrangement andcombination of parts may be resorted without departing from the spiritand scope of the invention as claimed. While the embodiments discussedherein may appear to include some limitations as to the presentation ofthe information units, in terms of the format and arrangement, theembodiments have applicability well beyond such embodiment, which can beappreciated by those skilled in the art. Accordingly, the scope of thepresent invention is defined by the appended claims rather than theforgoing description of embodiments.

The invention claimed is:
 1. A first playback device comprising: anetwork interface; at least one processor; a plurality of speakerdrivers; at least one orientation sensor; and tangible, non-transitorycomputer-readable memory including instructions stored therein, whereinthe instructions, when executed by the at least one processor, cause thefirst playback device to perform functions comprising: while the firstplayback device is in a first orientation, playing audio contentreceived via the network interface according to a first equalizationsetting; based on at least one signal from the orientation sensor,determining that the first playback device has changed from the firstorientation to a second orientation; and after determining that thefirst playback device has changed from the first orientation to thesecond orientation, playing the audio content received via the networkinterface according to a second equalization setting, wherein playingthe audio content received via the network interface according to thesecond equalization setting comprises playing only one channel of theaudio content in synchrony with a second playback device, wherein theaudio content comprises two or more channels.
 2. The first playbackdevice of claim 1, wherein playing audio content received via thenetwork interface according to the first equalization setting furthercomprises playing a first range of frequencies of the audio content, andwherein playing the audio content received via the network interfaceaccording to the second equalization setting further comprises playing asecond range of frequencies of the audio content.
 3. The first playbackdevice of claim 1, wherein the functions further comprise: in responseto determining that the first playback device has changed from the firstorientation to the second orientation, transmitting an indication of achange in orientation to a network device via the network interface. 4.The first playback device of claim 1, wherein the functions furthercomprise: in response to determining that the first playback device haschanged from the first orientation to the second orientation,transmitting an indication of a change in orientation to the secondplayback device via the network interface, wherein transmitting theindication of the change in orientation to the second playback devicevia the network interface causes the second playback device to changeone or more of (i) an equalization setting of the second playbackdevice, or (ii) a frequency range output by the second playback device.5. The first playback device of claim 1, wherein playing the audiocontent received via the network interface according to the firstequalization setting comprises receiving the audio content via thenetwork interface after the first equalization setting has been appliedby another network device.
 6. The first playback device of claim 1,wherein playing the audio content received via the network interfaceaccording to the first equalization setting comprises (i) receiving theaudio content, (ii) applying the first equalization setting to the audiocontent, and (iii) playing the audio content according to the firstequalization setting.
 7. The first playback device of claim 1, whereinplaying the audio content received via the network interface accordingto the first equalization setting comprises playing the audio content inmonaural.
 8. The first playback device of claim 1, wherein playing theaudio content received via the network interface according to the secondequalization setting comprises playing the audio content in stereo. 9.The first playback device of claim 1, wherein playing the audio contentreceived via the network interface according to the second equalizationsetting comprises playing a left channel of the audio content insynchrony with the second playback device playing back a right channelof the audio content.
 10. The first playback device of claim 1, whereinthe first equalization setting comprises one or more settings for thefirst playback device to play the audio content by itself, and whereinthe second equalization setting comprises one or more settings for thefirst playback device to play the audio content in synchrony with thesecond playback device.
 11. Tangible, non-transitory computer-readablemedia including instructions stored therein, wherein the instructions,when executed by at least one processor, cause a first playback deviceto perform functions comprising: while the first playback device is in afirst orientation, playing audio content received via a networkinterface of the first playback device according to a first equalizationsetting; based on at least one signal from an orientation sensor of thefirst playback device, determining that the first playback device haschanged from the first orientation to a second orientation; and afterdetermining that the first playback device has changed from the firstorientation to the second orientation, playing the audio contentreceived via the network interface according to a second equalizationsetting, wherein playing the audio content received via the networkinterface according to the second equalization setting comprises playingonly one channel of the audio content in synchrony with a secondplayback device, wherein the audio content comprises two or morechannels.
 12. The tangible, non-transitory computer-readable media ofclaim 11, wherein playing audio content received via the networkinterface according to the first equalization setting further comprisesplaying a first range of frequencies of the audio content, and whereinplaying the audio content received via the network interface accordingto the second equalization setting further comprises playing a secondrange of frequencies of the audio content.
 13. The tangible,non-transitory computer-readable media of claim 11, wherein thefunctions further comprise: in response to determining that the firstplayback device has changed from the first orientation to the secondorientation, transmitting an indication of a change in orientation to anetwork device via the network interface.
 14. The tangible,non-transitory computer-readable media of claim 11, wherein thefunctions further comprise: in response to determining that the firstplayback device has changed from the first orientation to the secondorientation, transmitting an indication of a change in orientation tothe second playback device via the network interface, whereintransmitting the indication of the change in orientation to the secondplayback device via the network interface causes the second playbackdevice to change one or more of (i) an equalization setting of thesecond playback device, or (ii) a frequency range output by the secondplayback device.
 15. The tangible, non-transitory computer-readablemedia of claim 11, wherein playing the audio content received via thenetwork interface according to the first equalization setting comprisesreceiving the audio content via the network interface after the firstequalization setting has been applied by another network device.
 16. Thetangible, non-transitory computer-readable media of claim 11, whereinplaying the audio content received via the network interface accordingto the first equalization setting comprises (i) receiving the audiocontent, (ii) applying the first equalization setting to the audiocontent, and (iii) playing the audio content according to the firstequalization setting.
 17. The tangible, non-transitory computer-readablemedia of claim 11, wherein playing the audio content received via thenetwork interface according to the first equalization setting comprisesplaying the audio content in monaural.
 18. The tangible, non-transitorycomputer-readable media of claim 11, wherein playing the audio contentreceived via the network interface according to the second equalizationsetting comprises playing the audio content in stereo.
 19. The tangible,non-transitory computer-readable media of claim 11, wherein playing theaudio content received via the network interface according to the secondequalization setting comprises playing a left channel of the audiocontent in synchrony with the second playback device playing back aright channel of the audio content.
 20. The tangible, non-transitorycomputer-readable media of claim 11, wherein the first equalizationsetting comprises one or more settings for the first playback device toplay the audio content by itself, and wherein the second equalizationsetting comprises one or more settings for the first playback device toplay the audio content in synchrony with the second playback device.